Introduction of the National Institute of Mental Health's Research Domain Criteria and revision of diagnostic classification for Autism Spectrum Disorder in the latest diagnostic manual call for a new way of conceptualizing heterogeneous ASD features. We propose a novel conceptualization of ASD, borrowing from the schizophrenia literature in…

Social-emotional behavior in autism spectrum disorder (ASD) was examined among high-risk (HR; siblings of children diagnosed with ASD) and low-risk (LR; no family history of ASD) toddlers. Caregivers completed the Infant-Toddler Social Emotional Assessment (ITSEA) at 18 months, and blind diagnostic assessment for ASD was conducted at 36 months.…

Existing models of autism spectrum disorder (ASD) disagree as to whether the core features should be conceptualized as convergent (related) or divergent (unrelated), and the few previous studies addressing this question have found conflicting results. We examined standardized parent ratings of symptoms from three domains (social, communication,…

The Study to Explore Early Development (SEED) is a multi-site case-control study designed to explore the relationship between autism spectrum disorder (ASD) phenotypes and etiologies. The goals of this paper are to (1) describe the SEED algorithm that uses the Autism Diagnostic Interview-Revised (ADI-R) and Autism Diagnostic Observation Schedule…

Efforts to understand the causes of autism spectrum disorders (ASDs) have been hampered by genetic complexity and heterogeneity among individuals. One strategy for reducing complexity is to target endophenotypes, simpler biologically based measures that may involve fewer genes and constitute a more homogenous sample. A genome-wide association…

In the present work, we have undertaken a proof-of-concept study to determine whether a simple upper-limb movement could be useful to accurately classify low-functioning children with autism spectrum disorder (ASD) aged 2-4. To answer this question, we developed a supervised machine-learning method to correctly discriminate 15 preschool children…

Objective: There is clinical heterogeneity among the autism spectrum disorders (ASD). The presence of dysmorphology (minor physical anomalies; MPAs) is one possible tool for defining a clinically relevant subset in ASD. This study employs an adaptation of Miles and Hillman's (2000) classifications by using photographs to identify a subgroup with…

New research findings provide major challenges regarding our understanding of the concept of autism. These are critically discussed in relation to research relevant to classification, genetics, environmental risk factors, gene-environment interplay, animal models, biomarkers, clinical features, neuropathology, pharmacotherapy, behavioral…

Background: Siblings of children with autism (sibs-A) are at increased genetic risk for autism spectrum disorders (ASD) and milder impairments. To elucidate diversity and contour of early developmental trajectories exhibited by sibs-A, regardless of diagnostic classification, latent class modeling was used. Methods: Sibs-A (N = 204) were assessed…

Autism is widely believed to be a heterogeneous disorder; diagnosis is currently based solely on clinical criteria, although genetic, as well as environmental, influences are thought to be prominent factors in the etiology of most forms of autism. Our goal is to determine whether a predictive model based on single-nucleotide polymorphisms (SNPs)…

The phenotypic heterogeneity of adults suspected of autism spectrum disorder (ASD) requires a standardized diagnostic approach that is feasible in all clinical settings. The autism mental status exam (AMSE) is an eight-item observational assessment that structures the observation and documentation of social, communicative and behavioral signs and…

Examined autism spectrum disorder (ASD) and schizophrenia spectrum disorder (SSD) symptoms in a clinically referred, non-ASD sample (N = 1160; ages 6-18) with and without oppositional defiant disorder (ODD). Mothers and teachers completed "DSM-IV"-referenced symptom checklists. Youth with ODD were subdivided into angry/irritable symptom (AIS) or…

Background: The nosology of autism spectrum disorders (ASD) is at a critical point in history as the field seeks to better define dimensions of social-communication deficits and restricted/repetitive behaviors on an individual level for both clinical and neurobiological purposes. These different dimensions also suggest an increasing need for…

Over the last decade, researchers have continued to make breakthroughs in understanding the clinical significance of motor symptoms in neurodevelopmental disorders, in particular, autism. With funding now available for assessment and therapy via the Federal Government's "Helping Children with Autism" initiative, there is an increased need for…

The current study examined the association between prenatal pregnancy complications (PPC) and childhood psychiatric symptoms in children with an autism spectrum disorder (ASD) and non-ASD children who were referred to a psychiatric clinic (Controls). Parents completed a "DSM-IV"-referenced rating scale and developmental history questionnaire.…